/*!
 * FullCalendar v2.4.0 Google Calendar Plugin
 * Docs & License: http://fullcalendar.io/
 * (c) 2015 Adam Shaw
 */

(function (factory) {
    if (typeof define === 'function' && define.amd) {
        define(['jquery'], factory);
    }
    else if (typeof exports === 'object') { // Node/CommonJS
        module.exports = factory(require('jquery'));
    }
    else {
        factory(jQuery);
    }
})(function ($) {


    var API_BASE = 'https://www.googleapis.com/calendar/v3/calendars';
    var fc = $.fullCalendar;
    var applyAll = fc.applyAll;


    fc.sourceNormalizers.push(function (sourceOptions) {
        var googleCalendarId = sourceOptions.googleCalendarId;
        var url = sourceOptions.url;
        var match;

        // if the Google Calendar ID hasn't been explicitly defined
        if (!googleCalendarId && url) {

            // detect if the ID was specified as a single string.
            // will match calendars like "asdf1234@calendar.google.com" in addition to person email calendars.
            if (/^[^\/]+@([^\/\.]+\.)*(google|googlemail|gmail)\.com$/.test(url)) {
                googleCalendarId = url;
            }
            // try to scrape it out of a V1 or V3 API feed URL
            else if (
                (match = /^https:\/\/www.googleapis.com\/calendar\/v3\/calendars\/([^\/]*)/.exec(url)) ||
                (match = /^https?:\/\/www.google.com\/calendar\/feeds\/([^\/]*)/.exec(url))
            ) {
                googleCalendarId = decodeURIComponent(match[1]);
            }

            if (googleCalendarId) {
                sourceOptions.googleCalendarId = googleCalendarId;
            }
        }


        if (googleCalendarId) { // is this a Google Calendar?

            // make each Google Calendar source uneditable by default
            if (sourceOptions.editable == null) {
                sourceOptions.editable = false;
            }

            // We want removeEventSource to work, but it won't know about the googleCalendarId primitive.
            // Shoehorn it into the url, which will function as the unique primitive. Won't cause side effects.
            // This hack is obsolete since 2.2.3, but keep it so this plugin file is compatible with old versions.
            sourceOptions.url = googleCalendarId;
        }
    });


    fc.sourceFetchers.push(function (sourceOptions, start, end, timezone) {
        if (sourceOptions.googleCalendarId) {
            return transformOptions(sourceOptions, start, end, timezone, this); // `this` is the calendar
        }
    });


    function transformOptions(sourceOptions, start, end, timezone, calendar) {
        var url = API_BASE + '/' + encodeURIComponent(sourceOptions.googleCalendarId) + '/events?callback=?'; // jsonp
        var apiKey = sourceOptions.googleCalendarApiKey || calendar.options.googleCalendarApiKey;
        var success = sourceOptions.success;
        var data;
        var timezoneArg; // populated when a specific timezone. escaped to Google's liking

        function reportError(message, apiErrorObjs) {
            var errorObjs = apiErrorObjs || [{message: message}]; // to be passed into error handlers

            // call error handlers
            (sourceOptions.googleCalendarError || $.noop).apply(calendar, errorObjs);
            (calendar.options.googleCalendarError || $.noop).apply(calendar, errorObjs);

            // print error to debug console
            fc.warn.apply(null, [message].concat(apiErrorObjs || []));
        }

        if (!apiKey) {
            reportError("Specify a googleCalendarApiKey. See http://fullcalendar.io/docs/google_calendar/");
            return {}; // an empty source to use instead. won't fetch anything.
        }

        // The API expects an ISO8601 datetime with a time and timezone part.
        // Since the calendar's timezone offset isn't always known, request the date in UTC and pad it by a day on each
        // side, guaranteeing we will receive all events in the desired range, albeit a superset.
        // .utc() will set a zone and give it a 00:00:00 time.
        if (!start.hasZone()) {
            start = start.clone().utc().add(-1, 'day');
        }
        if (!end.hasZone()) {
            end = end.clone().utc().add(1, 'day');
        }

        // when sending timezone names to Google, only accepts underscores, not spaces
        if (timezone && timezone != 'local') {
            timezoneArg = timezone.replace(' ', '_');
        }

        data = $.extend({}, sourceOptions.data || {}, {
            key: apiKey,
            timeMin: start.format(),
            timeMax: end.format(),
            timeZone: timezoneArg,
            singleEvents: true,
            maxResults: 9999
        });

        return $.extend({}, sourceOptions, {
            googleCalendarId: null, // prevents source-normalizing from happening again
            url: url,
            data: data,
            startParam: false, // `false` omits this parameter. we already included it above
            endParam: false, // same
            timezoneParam: false, // same
            success: function (data) {
                var events = [];
                var successArgs;
                var successRes;

                if (data.error) {
                    reportError('Google Calendar API: ' + data.error.message, data.error.errors);
                }
                else if (data.items) {
                    $.each(data.items, function (i, entry) {
                        var url = entry.htmlLink;

                        // make the URLs for each event show times in the correct timezone
                        if (timezoneArg) {
                            url = injectQsComponent(url, 'ctz=' + timezoneArg);
                        }

                        events.push({
                            id: entry.id,
                            title: entry.summary,
                            start: entry.start.dateTime || entry.start.date, // try timed. will fall back to all-day
                            end: entry.end.dateTime || entry.end.date, // same
                            url: url,
                            location: entry.location,
                            description: entry.description
                        });
                    });

                    // call the success handler(s) and allow it to return a new events array
                    successArgs = [events].concat(Array.prototype.slice.call(arguments, 1)); // forward other jq args
                    successRes = applyAll(success, this, successArgs);
                    if ($.isArray(successRes)) {
                        return successRes;
                    }
                }

                return events;
            }
        });
    }


// Injects a string like "arg=value" into the querystring of a URL
    function injectQsComponent(url, component) {
        // inject it after the querystring but before the fragment
        return url.replace(/(\?.*?)?(#|$)/, function (whole, qs, hash) {
            return (qs ? qs + '&' : '?') + component + hash;
        });
    }


});
